Reset Navigator state

[Guardiola31337]

Description

Resets Navigator when in on TripSession#stop and renames DirectionsSession shutdown API

Fixes #2769

• I have added any issue links
• I have added all related labels (bug, feature, new API(s), SEMVER, etc.)
• I have added the appropriate milestone and project boards

Goal

As MapboxNativeNavigatorImpl is a singleton (object) Navigator is retained between sessions causing unexpected behaviors as the internal cache is not reset

Implementation

• Add reset API to MapboxNativeNavigator and recreate Navigator when MapboxNativeNavigatorImpl#reset
• Rename MapboxDirectionsSession shutdown API from shutdownSession to shutdown

Testing

• I have tested locally (including SNAPSHOT upstream dependencies if needed) through testapp/demo app and run all activities to avoid regressions
• I have tested via a test drive, or a simulation/mock location app
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have updated the CHANGELOG including this PR

cc @kmadsen @cafesilencio @SiarheiFedartsou

[codecov-io]

Codecov Report

Merging #2850 into master will decrease coverage by 0.00%.
The diff coverage is 40.00%.

@@             Coverage Diff              @@
##             master    #2850      +/-   ##
============================================
- Coverage     35.43%   35.43%   -0.01%     
  Complexity     2101     2101              
============================================
  Files           544      544              
  Lines         19536    19539       +3     
  Branches       1841     1841              
============================================
+ Hits           6922     6923       +1     
- Misses        11788    11790       +2     
  Partials        826      826              

[kmadsen]

probably want to reset the other things, like route